How to proceed with image processing in GUI?

I have set up a GUI whereby the first push button(Load a MRI image) is to allow the user to select any image. I would like to proceed with image processing using the selected image from the first pushbutton. I have other pushbuttons like 'image enhancement', 'roi detection'. How can I proceed with image processing using the selected image from the first pushbutton?

Answer 1

[Walter Roberson]

http://matlab.wikia.com/wiki/FAQ#How_can_I_share_data_between_callback_functions_in_my_GUI.3F

[Gee Cheng Mun]

I tried but I don't understand. I can't save the image and process it under the second pushbutton.

% --- Executes on button press in load_mri.

function load_mri_Callback(hObject, eventdata, handles)

path='G:\FYP2\';

filter='*.png;*.jpg;*.tif;*.png;*.gif';'All Image Files';

[selectedFile, selectedPath]=uigetfile(fullfile(path, filter));

handles.img=imread([selectedPath, selectedFile]);

axes(handles.axes2);

image(handles.img);

setappdata(load_mri, 'Load MRI Image'); %save the application data

% --- Executes on button press in enhancement.

function enhanchObjectement_Callback(hObject, eventdata, handles)

yourVariable = getappdata(load_mri, 'Load MRI Image')

mri=imread(yourVariable);

gray=rgb2gray(mri);

I=imadjust(gray);

imshow(I);

Answer 2

[Walter Roberson]

Below I show proper use of both handles and setappdata

% --- Executes on button press in load_mri.
function load_mri_Callback(hObject, eventdata, handles)

    path='G:\FYP2\';
    filter='*.png;*.jpg;*.tif;*.png;*.gif';'All Image Files';

    [selectedFile, selectedPath]=uigetfile(fullfile(path, filter));

    [~, image_name, ~] = basename(selectedFile);
    image_file = fullfile(selectedPath, selectedFile);
    image_data = imread(image_name);

    axes(handles.axes2);
    image(image_data);

    %image name is small, you can afford to store it in handles
    handles.image_name = image_name;
    handles.image_file = image_file;
    guidata(hObject, handles);

    %image content could be big, do not store it in handles
    myfig = ancestor(hObject, 'figure');
    setappdata(myfig, 'Loaded_MRI_Image', image_data); %save the application data

% --- Executes on button press in enhancement.
function enhanchObjectement_Callback(hObject, eventdata, handles)

    myfig = ancestor(hObject, 'figure');
    mri = getappdata(myfig, 'Loaded_MRI_Image');   %it is already the image
    image_name = handles.image_name;

    gray = rgb2gray(mri);
    I = imadjust(gray); 
    imshow(I);
    title( sprintf('Contrast adjusted "%s"', image_name) );

[Gee Cheng Mun]

I tried your code and I am not able to display the image. Initially, the code allows me to display this image. However, now it is not able to.

Undefined function 'basename' for input arguments of type 'char'.

Error in Finaldraft>load_mri_Callback (line 81) [~, image_name, ~] = basename(selectedFile);

Error in gui_mainfcn (line 95) feval(varargin{:});

Error in Finaldraft (line 42) gui_mainfcn(gui_State, varargin{:});

Error in @(hObject,eventdata)Finaldraft('load_mri_Callback',hObject,eventdata,guidata(hObject))

Error while evaluating uicontrol Callback

[Walter Roberson]

Sorry, I should have used the function fileparts instead of basename

   [~, image_name, ~] = fileparts(selectedFile);

[Gee Cheng Mun]

I am now able to load the image but not able to process it under enhancement, using the same loaded image.

Error using feval Undefined function 'enhancement_Callback' for input arguments of type 'struct'.

Error in gui_mainfcn (line 95) feval(varargin{:});

Error in Finaldraft (line 42) gui_mainfcn(gui_State, varargin{:});

Error in @(hObject,eventdata)Finaldraft('enhancement_Callback',hObject,eventdata,guidata(hObject))

Error while evaluating uicontrol Callback

myfig = ancestor(hObject, 'figure');
mri = getappdata(myfig, 'Load_MRI_Image', image_data);   %it is already the image
gray = rgb2gray(mri);
I = imadjust(gray); 
imshow(I);
title( sprintf('Contrast adjusted "%s"', image_name) );

[Image Analyst]

enhancement_Callback is not spelled the same as enhanchObjectement_Callback, so which is it? Which is the right name?

Answer 3

[Image Analyst]

You might try MAGIC: http://www.mathworks.com/matlabcentral/fileexchange/24224-magic-matlab-generic-imaging-component All that stuff is already worked out for you. You just put your analysis code into the function AnalyzeSingleImage. It handles all the rest from listing image names in a listbox to displaying them to batch processing them to sending results to Excel.